York Screw Chiller YCIV0307VA46

Install a high-quality, high-resolution analog pressure gauge on one of the service valves

All system valves including manual valves and EEVs are 100% open

All valves to the atmosphere are closed with flare caps in place

Unit is at the initial evacuation level of 5 mmHg

Charge with a vapor only for a 10% trace gas, R-134a based on nameplate, into the chiller until the system pressure reaches 10 psig (69 kPa)

Connect hoses to the high and low side of the system and add dry nitrogen into the chiller until the pressure reaches 100 psig (690 kPa)

Concentration of trace gas has reached all parts of the system

Any vented gas has been adequately vented from the chiller area

Test around each joint and factory weld

Warning: This procedure must be performed by an industry certified technician who has been trained and qualified to work on this type of equipment.

A record of this procedure being successfully carried out should be maintained on file by the equipment owner should proof of adequate maintenance be required at a later date for warranty purposes.

Sample compressor oil, check for acid, and replace if necessary.

Disconnect power source and lock out and check tightness of power wiring connections.

Check glycol concentration on low temperature or other applications where freezing may be a problem.

Check programmable operating setpoints and safety cutouts and ensure they are correct for the application

Check compressor and evaporator heater operation

Check for dirt in the control panel and check door gasket sealing integrity

Check oil level in the oil separator sight glass

Check liquid line sight glass / moisture indicator

Record system operating temperatures

Record system operating pressures

Check condenser coils for dirt/debris

Clean condenser coils if necessary

Sign off on the weekly chiller check

Connect a high-capacity vacuum pump with indicator to the charging valves

Ensure all the system valves including manual valves and EEVs are 100% open

Ensure that all valves to the atmosphere are closed with flare caps in place, if applicable

Operate the vacuum pump until a pressure of 5,000 μm is reached

To start the 8-hour vacuum hold test, close the system charging valve connection to the vacuum pump

Hold the vacuum obtained in Step 4 in the system for 8 hours

Check for pressure change with the chiller at the same temperature